Legionella safety

Legionellosis is a collective term for diseases caused by Legionella bacteria. The most serious, Legionnaires’ disease is a potentially fatal form of pneumonia. Everyone is susceptible to infection, however risks are increased with age, in heavy drinkers, smokers and in people with certain health conditions (e.g. diabetes, respiratory conditions and conditions that affect the immune system). Other similar but less serious conditions are Pontiac fever and Lochgoilhead fever.

The bacteria that causes Legionellosis are common in natural water sources such as rivers, lakes and reservoirs, but usually in low numbers. They may also be found in purpose-built water systems such as hot and cold water systems and spa pools. If conditions are favourable, the bacteria may grow, increasing the risks of Legionnaires’ disease. Exposure is usually through inhaling contaminated water when it's dispersed in the air as an aerosol.

The legal requirements for the control of Legionella is covered by the Control of Substances Hazardous to Health Regulations 2002 and the HSE Approved Code of Practice: Legionnaires' disease. The control of legionella bacteria in water systems (L8).


The risks from Legionella increase if:

  • the water temperature in all or some parts of the water system is between 20-45 °C, which is suitable for growth
  • it's possible for breathable water droplets to be created and dispersed e.g. aerosols created by water outlets
  • water is stored and/or re-circulated
  • there are deposits that can support bacterial growth by providing a source of nutrients for the organism, e.g. rust, sludge, scale, organic matter and biofilms

How we manage the risk of Legionellosis

The University is required by law to have appropriate measures in place to control the risk of Legionellosis. Our Legionella Management Policy and Plan (.pdf) sets out our arrangements for managing:

  • roles and responsibilities
  • requirements for training
  • how risks are assessed and controlled
  • record keeping
  • the action that will be taken in the event of water sample monitoring indicating a higher than expected microbial count

Common methods of controlling risk in hot and cold water systems is by maintaining water temperatures so they are outside the above range, regular descaling, and flushing little used water outlets to ensure water cannot stagnate. Regular monitoring is needed to ensure these control measures are effective.

Our responsibilities

Overall responsibility 

The Registrar and Secretary is the duty holder with overall responsibility for ensuring that there are effective arrangements in place and that adequate resources are allocated to the control of Legionella on the University’s Estate.

Responsibility for managing the risk of Legionella 

The Estate Management Section has prime responsibility for managing risks from Legionella within fixed water systems that are part of the “built environment” across the University's estate. Specific responsibilities are detailed in the Legionella Management Policy and Plan (.pdf).

Heads of Department/Section/ Faculty responsibilities

  • Control the risks arising from Legionella where it relates to activities and equipment outside of the “built environment”, including stand-alone equipment holding or circulating water.
  • Inform the Estate Management Section of little used water outlets in your area of responsibility.
  • Supporting the Estate Management Section in meeting its responsibilities in relation to the management of Legionella risk across the University's estate.

All staff responsibilities 

  • If you have sinks, showers or other water outlets in your area of responsibility that are used less than weekly. A regular flushing regime will be necessary to prevent Legionella build up. You will need to inform us so that a flushing system can be set up.
  • If you're responsible for equipment that holds or circulates water, you will need to check whether there is a Legionella risk and, if so, implement suitable controls. If you are unsure contact the Health and Safety Advisory Service for advice.
  • Some areas will need to be visited regularly to carry out flushing, descaling and, where necessary, other remedial work. Your assistance may be needed in gaining access to affected water outlets.
  • If you have been given responsibility for flushing, cleaning or scale removal you have a responsibility to attend training and follow safe working procedures for the control of Legionella.

    Staff responsible for outlet flushing, cleaning or scale removal of shower heads must:

    • Attend appropriate Legionella awareness training.
    • Follow safe working procedure, including wearing personal protective equipment when required.
    • Keep accurate records of the checks you carry out.
    • Report any concerns you have with your manager.

    Symptoms of Legionnaires' disease

    The symptoms of Legionnaires' disease are similar to the symptoms of the flu:

    • high temperature, feverishness and chills
    • muscle pains
    • headache
    • tiredness
    • signs of mental confusion

    Leading on to symptoms of pneumonia such as:

    • a persistent cough
    • breathlessness
    • chest pain
    • pneumonia
    • vomiting

    If you develop the above symptoms and are worried that it might be Legionnaires' disease (because you have been exposed to spray or mist), see your GP. The illness is treatable with antibiotics. If you think exposure may have occurred while working at the University, tell your manager or the Health and Safety Advisory Service as soon as possible.

    Also see

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    Workplace Health, Safety and Wellbeing
    Telephone: 01206 872944